The present invention relates to a liner which is used with an explosive charge.
Shaped explosive charges which use metal liners are commonly made in a wide variety of designs, sizes and functions and are commonly used in military warheads, underwater projects, oil drilling operations, mining, demolition, and construction projects. The shaped charge liners are currently manufactured by conventional metal forming and machining processes. These manufacturing processes result in the liner having a polycrystalline microstructure.
The polycrystalline microstructure of known liners can have a wide range of grain sizes and morphologies. The mechanical properties of these components are primarily isotropic (non-directional). However, it has been recognized that the performance of an explosive device can be significantly affected by differences in grain size and morphology. In particular, it has been found that certain crystallographic textures, which result from prior forming processes, tend to enhance performance. It has also been found that grain size and uniformity can significantly affect performance.
Because of the polycrystalline nature of traditional metals and alloys, the designer of liners for use with explosive charges, whether of the self-forging fragment type or jet type, has been limited in his ability to control the crystal microstructure of the liner. With a polycrystalline microstructure, grain boundaries are present and crystallographic orientation within the plurality of grains cannot be controlled to a high degree. Some degree of control over grain size, grain morphology and crystallographic texture has been obtained by carefully controlled processing, but these efforts have been limited by the basic nature of the polycrystalline material. Similarly, because of the polycrystalline nature of conventional shaped charge liners, uniformity of structure from batch-to-batch and part-to-part cannot always be controlled to the extent desired to assure repeatable explosive deformation and jet formation.